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991.
A group of asymptomatic microfilaraemic individuals (n = 44, 29 males, 15 females) living in a Wuchereria bancrofti endemic region of Orissa, India, was treated with a standard regimen of diethylcarbamazine (12 days, 6 mg/kg) in 1990. The incidence of microfilaraemia and antigenemia (Og4C3) was determined after a gap of 10 years in 2000. Nineteen individuals reacquired microfilariae (43.2%, 11 males, eight females), five males developed hydrocele, two females became acute filarial patients and 18 subjects (13 males, five females) were asymptomatic amicrofilaraemics. Filarial antigen was detected in 36 individuals (81.2%, 27 male, nine female) comprising microfilaraemics, amicrofilaraemics and diseased. Only eight individuals (18.2%, two males, six females) remained antigen free. 相似文献
992.
Characterization of 13 novel band 3 gene defects in hereditary spherocytosis with band 3 deficiency 总被引:8,自引:3,他引:8
Jarolim P; Murray JL; Rubin HL; Taylor WM; Prchal JT; Ballas SK; Snyder LM; Chrobak L; Melrose WD; Brabec V; Palek J 《Blood》1996,88(11):4366-4374
Hereditary spherocytosis (HS) is a common hemolytic anemia of variable clinical expression. Pathogenesis of HS has been associated with defects of several red cell membrane proteins including erythroid band 3. We have studied erythrocyte membrane proteins in 166 families with autosomal dominant HS. We have detected relative deficiency of band 3 in 38 kindred (23%). Band 3 deficiency was invariably associated with mild autosomal dominant spherocytosis and with the presence of pincered red cells in the peripheral blood smears of unsplenectomized patients. We hypothesized that this phenotype is caused by band 3 gene defects. Therefore, we screened band 3 DNA from these 38 kindred for single strand conformational polymorphisms (SSCP). In addition to five mutations detected previously by SSCP screening of cDNA, we detected 13 new band 3 gene mutations in 14 kindred coinherited with HS. These novel mutations consisted of two distinct subsets. The first subset included seven nonsense and frameshift mutations that were all associated with the absence of the mutant mRNA allele from reticulocyte RNA, implicating decreased production and/or stability of mutant mRNA as the cause of decreased band 3 synthesis. The second group included five substitutions of highly conserved amino acids and one in-frame deletion. These six mutations were associated with the presence of comparable levels of normal and mutant band 3 mRNA. We suggest that these mutations interfere with band 3 biosynthesis leading thus to the decreased accumulation of the mutant band 3 allele in the plasma membrane. 相似文献
993.
Lissoni P Tancini G Paolorossi F Mandalà M Ardizzoia A Malugani F Giani L Barni S 《Journal of pineal research》1999,26(3):169-173
Thrombocytopenia is a frequent complication of cancer and constitutes an absolute contraindication for chemotherapy. Recent studies have demonstrated that platelet generation may be influenced by both cytokines and neurohormones. In particular, the pineal indole melatonin has been proven to enhance platelet number in patients with thrombocytopenia due to different reasons. On this basis, we have evaluated the effects of a concomitant administration of melatonin in thrombocytopenic cancer patients undergoing chemotherapy. The study was performed in 14 metastatic breast cancer women treated by weekly epirubicin. Each cycle consisted of epirubicin at 25 mg/m2 i.v. at weekly intervals. Melatonin was given orally at 20 mg/day in the evening every day, starting 7 days prior to chemotherapy. Patients were considered as evaluable when they received at least four cycles of chemotherapy. Evaluable patients were 12/14. The induction phase with melatonin induced a normalization of platelet number in 9/12 evaluable patients, and no further platelet decline occurred in chemotherapy. Objective tumor regression was achieved in 5/12 (41%) patients. This preliminary study would suggest that melatonin may be effective in the treatment of cancer-related thrombocytopenia and to prevent chemotherapy-induced platelet decline. Until now, melatonin therapy of cancer has been generally considered as an alternative treatment to chemotherapy. In contrast, this study would suggest that melatonin may contribute to the realization of chemotherapy in metastatic cancer patients unable to tolerate the chemotherapeutic approach because of persistent thrombocytopenia. 相似文献
994.
The bile acid-activated phosphatidylinositol 3-kinase pathway inhibits Fas apoptosis upstream of bid in rodent hepatocytes 总被引:6,自引:0,他引:6
Takikawa Y Miyoshi H Rust C Roberts P Siegel R Mandal PK Millikan RE Gores GJ 《Gastroenterology》2001,120(7):1810-1817
BACKGROUND & AIMS: Bile acids differentially modulate hepatocyte injury in cholestasis. Although glycochenodeoxycholate (GCDC) induces Fas-mediated hepatocyte apoptosis, taurochenodeoxycholate (TCDC) simultaneously activates a phosphatidylinositol 3-kinase (PI 3-K)-mediated survival pathway blocking Fas apoptosis. In this study, the mechanisms by which the TCDC/PI 3-K survival signal disrupts Fas signaling were examined. METHODS: Studies were performed in primary cultures of mouse hepatocytes and the bile-salt-transporting McNtcp.24 rat hepatoma cell line. RESULTS: GCDC, but not TCDC, resulted in cytochrome c release demonstrating that TCDC blocked apoptosis upstream of mitochondria. In contrast, both GCDC and TCDC treatment resulted in Fas aggregation and recruitment of a dominant-negative FADD green fluorescent protein (GFP) and C360S procaspase 8-GFP to the plasma membrane. Despite recruitment of procaspase 8 to the plasma membrane by both bile acids, only GCDC resulted in increases of caspase 8 activity and Bid-GFP mitochondrial translocation. However, when PI-3K was inhibited with wortmannin or dominant-negative PI 3-K, TCDC-induced Bid-GFP mitochondrial translocation and cytochrome c release. CONCLUSIONS: The TCDC/PI 3-K survival signal blocks Fas-mediated apoptosis by preventing caspase 8 activation and Bid mitochondrial translocation. Potentiation of this survival pathway in cholestasis has the potential to attenuate liver injury. 相似文献
995.
The complement fragment C5a and the cytokine interleukin-8 (IL-8) are proinflammatory peptides with potent chemotactic activity toward neutrophils. We have previously shown that C5a can be inactivated by a protease that is found in normal synovial and peritoneal fluids but is absent from serosal fluids obtained from patients with familial Mediterranean fever (FMF). We report here that serosal fluids can also eliminate the chemotactic activity of IL-8. The agent responsible for IL-8 elimination appears to be the C5a-inactivating protease, because the pure protease can inactivate IL-8, inactivation of IL-8 by normal peritoneal fluid is partly prevented by an antibody raised against the purified C5a-inactivating protease, and IL-8 is not inactivated by peritoneal fluids from patients with FMF. The ability of this protease to inactivate both, early (C5a) and late (IL-8) inflammatory mediators identifies it as a potentially significant regulator of inflammation. 相似文献
996.
Loss of transformed phenotype in cancer cells by overexpression of the uteroglobin gene 总被引:3,自引:0,他引:3
Zhang Z Kundu GC Panda D Mandal AK Mantile-Selvaggi G Peri A Yuan CJ Mukherjee AB 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(7):3963-3968
Uteroglobin (UG) is a multifunctional, secreted protein that has receptor-mediated functions. The human UG (hUG) gene is mapped to chromosome 11q12.2-13.1, a region frequently rearranged or deleted in many cancers. Although high levels of hUG expression are characteristic of the mucosal epithelia of many organs, hUG expression is either drastically reduced or totally absent in adenocarcinomas and in viral-transformed epithelial cells derived from the same organs. In agreement with these findings, in an ongoing study to evaluate the effects of aging on UG-knockout mice, 16/16 animals developed malignant tumors, whereas the wild-type littermates (n = 25) remained apparently healthy even after 11/2 years. In the present investigation, we sought to determine the effects of induced-expression of hUG in human cancer cells by transfecting several cell lines derived from adenocarcinomas of various organs with an hUG-cDNA construct. We demonstrate that induced hUG expression reverses at least two of the most important characteristics of the transformed phenotype (i.e., anchorage-independent growth on soft agar and extracellular matrix invasion) of only those cancer cells that also express the hUG receptor. Similarly, treatment of the nontransfected, receptor-positive adenocarcinoma cells with purified recombinant hUG yielded identical results. Taken together, these data define receptor-mediated, autocrine and paracrine pathways through which hUG reverses the transformed phenotype of cancer cells and consequently, may have tumor suppressor-like effects. 相似文献
997.
Barrick JE Corbino KA Winkler WC Nahvi A Mandal M Collins J Lee M Roth A Sudarsan N Jona I Wickiser JK Breaker RR 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(17):6421-6426
The expression of certain genes involved in fundamental metabolism is regulated by metabolite-binding "riboswitch" elements embedded within their corresponding mRNAs. We have identified at least six additional elements within the Bacillus subtilis genome that exhibit characteristics of riboswitch function (glmS, gcvT, ydaO/yuaA, ykkC/yxkD, ykoK, and yybP/ykoY). These motifs exhibit extensive sequence and secondary-structure conservation among many bacterial species and occur upstream of related genes. The element located upstream of the glmS gene in Gram-positive organisms functions as a metabolite-dependent ribozyme that responds to glucosamine-6-phosphate. Other motifs form complex folded structures when transcribed as RNA molecules and carry intrinsic terminator structures. These findings indicate that riboswitches serve as a major genetic regulatory mechanism for the control of metabolic genes in many microbial species. 相似文献
998.
Chronic prostatitis/chronic pelvic pain syndrome: national survey of genitourinary medicine clinics 总被引:3,自引:0,他引:3
Luzzi GA Bignell C Mandal D Maw RD;British Co-operative Clinical Group 《International journal of STD & AIDS》2002,13(6):416-419
We sought to determine current practice in the diagnosis and management of chronic prostatitis/chronic pelvic pain syndrome (CPPS) in genitourinary medicine departments in the UK, using a detailed questionnaire survey. Evaluable responses were received from 147 (69%) clinics. Seventy-nine (54%) clinics reported seeing >10 new CPPS patients per year. A broad range of investigations was reported to be used in the diagnosis of CPPS. Whilst 89 (61%) clinics reported using the four-glass test in diagnosis, 46 (32%) reported using the test in >90% of patients with CPPS, and 42 (29%) reported never using the test. In the treatment, doxycycline or ciprofloxacin were reported to be first line treatment by 98% clinics, mostly in 4-6 week courses; however, great variation was recorded in second-line choices and use of non-antibiotic approaches. This survey demonstrates that patients with CPPS are regularly diagnosed and managed in genitourinary clinics in the UK, with wide variations in diagnostic and treatment practices. 相似文献
999.
Splenectomy (SPLX) prevents ischemic acute tubular necrosis (ATN) and peritubular capillary (PTC) congestion. This study attempts to reverse the protective effect of splenectomy in the ischemic model of ATN by increasing hematocrit before inducing ATN. Sham-SPLX, SPLX, and SPLX dogs given packed red cells to elevate hematocrit by 30% (SPLX-high hematocrit) received bilateral renal artery obstruction (RAO) for 120 minutes. Renal function was tested for 6 days post-RAO. Hematocrit in the SPLX-high hematocrit group was greater (p less than .05) than the SPLX-RAO group but did not differ from the non-SPLX group. All groups had different (p less than .05) serum creatinine levels for 48 hours post-RAO, and untreated animals differed from all the others at 144 hours. Serum creatinine was highest in untreated, lowest in SPLX-high hematocrit, and intermediate in noninfused SPLX animals. The same pattern was observed in blood urea nitrogen, creatinine clearance and renal histopathology. Fractional excretion of sodium in the SPLX groups was six times that in the intact animals (p less than .05), irrespective of hematocrit level. We conclude that increased hematocrit is protective in ischemic ATN, and does not promote PTC congestion or ATN in the SPLX animal. In addition, the protective effect of splenectomy may be mediated, in part, by mechanism(s) that alter sodium transport or osmolar excretion. 相似文献
1000.
Sabyasachi Das Santanu Kar Mahapatra Satyajit Tripathy Sourav Chattopadhyay Sandeep Kumar Dash Debasis Mandal Balaram Das Amiya Kumar Hati Somenath Roy 《Antimicrobial agents and chemotherapy》2014,58(10):5909-5915
Malaria is a major public health problem in tropical and subtropical countries, including India. This study elucidates the cause of chloroquine treatment failure (for Plasmodium falciparum infection) before the introduction of artemisinin combination therapy. One hundred twenty-six patients were randomized to chloroquine treatment, and the therapeutic efficacy was monitored from days 1 to 28. An in vitro susceptibility test was performed with all isolates. Parasitic DNA was isolated, followed by PCR and restriction digestion of different codons of the pfcrt gene (codons 72 to 76) and the pfmdr1 gene (N86Y, Y184F, S1034C, N1042D, and D1246Y). Finally, sequencing was done to confirm the mutations. Forty-three (34.13%) early treatment failure cases and 16 (12.69%) late treatment failure cases were observed after chloroquine treatment. In vitro chloroquine resistance was found in 103 isolates (81.75%). Twenty-six (60.47%) early treatment failure cases and 6 (37.5%) late treatment failure cases were associated with the CVMNK-YYSNY allele (the underlined amino acids are those that were mutated). Moreover, the CVIEK-YYSNY allele was found in 8 early treatment failure (18.60%) and 2 late treatment failure (12.5%) cases. The presence of the wild-type pfcrt (CVMNK) and pfmdr1 (YYSNY) double mutant allele in chloroquine-nonresponsive cases was quite uncommon. In vivo chloroquine treatment failure and in vitro chloroquine resistance were strongly correlated with the CVMNK-YYSNY and CVIEK-YYSNY haplotypes (P < 0.01). 相似文献